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@uiten- ALONZO 'I'. BOON AND JAMES B. FINOHURE, Oli1 GALESBURG, ILLINOIS.

Letters Patent No. 80,589, dated August 4, 1868.'

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To ALL WHoM 1T MAY concurrir:A

Be it known that we, ALoivzo T. Boon and JAMES B. FINcHUnE, of the city of Galesburg, in the county of Knox, and State of Illinois, have invented a new and useful -Improvement in Dentists" and Barbers Chairs; and we do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the accompanying drawings, making a part of this specification, in which- Figure 1 is a sectional view of the chair. Figures 2 and 3 are views, in detail, of device for elevating and depressing the rear end thereof. Figures 4 and 5 are views, in detail, of device for adjusting head-rest. Like letters in the figures of the drawings indicate like parts. Our invention relates to a new and improved chair for the use of dentists or barbers. It consists ofthe ordinary'modcru easy-chair used by dentists and barbcrs, but having combined therewith an adjustable rest for the hea-d, together with a device by which the back'of the chair is held securely in a position more or less inclined, orA at an angle more or less acute, whereby persons of different sizes may recline thereon i'n that posture the vmost productive of their ease and comfort.

To enable any one skilled in the art to make and use our inventiomwe will pfoceed to describeits construction and operation'. f

i A represents a metallic support, which is rigidly attached to the rear and lower'portion of the chair,

and having therein an orifice, at either standard or upright thereof, for the support and rotation therein of a metallic rod.

Brepresents the aforesaid metallic rod, working in the said support, and having, on the exterior end thereof, a. knob, a, and upon its opposite extremity a helical screw. A

C represents a spiral spring, which is located between the metallic support A and the disk of the helical screw, and which impinges against the said disk, and thereby presses thc threads of the said helical 'screw into the teeth of the rack. i

D represents the. helical screw, designed and adapted to work into `the teeth of the rack, as shown, and which is rigidly attached to the rod I3.

E is the rack, which is pivotcd to the back and lower portion of the seat of the chair, andinto the cogs of which work thc threads of the helical screw. i

F represents the aforesaid adjustable head-rest, and it consists of a slightly-curved piece of wood or metal, whichis sometimes padded, but so shaped as to present a slightly-concave surface for the head to rest upon, and having projecting downwards therefrom a supporting-piece attached thereto, by=which it is elevated or lowered.

G represents a crank, thesmaller arm of which is cam-shaped, with a groove around the centre thereof, and a piece of rubber, c, ailxcd therein, in order to cause (when pressingthe handle of the crank downward) the aforesaid cam to impinge 4against andhold steadfastly in its place and position the standardof the head-rest, the rubber preventing the standard from slipping. i

II represents a metallic plate, which holds the aforesaid cam and crank within a suitable recess formed in the back of the chair for their reception.

I represents a pivot, it being the pivotcdpoint of the scat of the chair.

This invention is designed to overcome the great annoyance and evil attendant upon the use of chairs having adjustable seats, the said objection' arising from the difficulty with which they are adjusted into a position comfortable to the occupant without involvinghis frequently rising therefrom. Now, while the measure of the great power imparted by the helical screw. and rack is well known and obvious, it will also be readily perceived that the aforesaid pivotcd seat can readily and easily' be adjusted by the operator, however heavy the person may be occupying the chair.

Haring thus fully described our invention, whet we claim therein as new, and desire to secure by Letters Patent, is-

1. The combination and arrangement of the head-rest E, crank G, with a grooved cam, b, and rubber, c,

axed therein, und plate H, with the back of the chair, substantially in the manner 4and for the purpose as herein shown and deseribed.v f

2. The combination and arrangement of thesupport A, rod B, spiral spring C, helical screw D, and rack E,'with the seat of the chair, substantielly in the manner and for the purpose as herein shown and described.

` v .ALONZO T. BOON,

JAMES B. FINCHURE.

Witnesses:

LoREN STEVENS, ALBERT D. PERRY. 

